Carroll started his career in the editorial department where he worked as assistant and additional editor on projects such as the horror film Massacre at Central High (1976), the horror film Dracula's Dog (1978, starring Michael Pataki), and the thriller Roar (1981). In 1979 he wrote the horror thriller Tourist Trap on which he also worked as producer.

Further writing credits include the screenplay for the science fiction film The Day Time Ended (1980, with Marcy Lafferty), several episodes for the animated television series He-man and the Masters of the Universe (1985, with voice talents Alan Oppenheimer and Lou Scheimer), Silverhawks (1986), Thundercats (1986), Ghostbusters (1986-1987, with voice talents Alan Oppenheimer and Lou Scheimer), Dennis the Menace (1986, with voice talent Brian George), She-ra: Princess of Power (1986-1987, with Alan Oppenheimer and Lou Scheimer), The Comic Trip (1987), and BraveStarr (1987-1988, with Alan Oppenheimer and Lou Scheimer).

Carroll also worked as writer and supervising producer on the television series Diagnosis Murder (1997-1999) and Martial Law (1999-2000). More recently he wrote the stories for episodes of Pucca (2007) and Edgar & Ellen (2008).